BIOL 320 LAB PRACTICAL 2 EXAM 2025
QUESTIONS AND ANSWERS
Electrocardiogram ECG - ANS pattern of electrical activity recorded at the body surface
Cardiac Contractions are _______ on a nerve supply - ANS not dependent
Innervations by the _______ and ________ nerves modify the basic cardiac rhythms -
ANS parasympathetic;sympathetic; (thus the central nervous system can affect the rhythm
sinus arrhythmia - ANS respiratory activity affects the heart rate
sinoatrial node - ANS pacemaker of the heart
atrioventricular node - ANS the only electrical connection between the atria and the
ventricles
electrical stimulation through action potentials through the heart - ANS SA node --> AV node
(slowly to allow atrial contraction to contribute to ventricular filling)--> rapidly through the AV
bundle -- > Purkinje fibers to excite both ventricles
what aspect of cardiac action potential distinguishes it from skeletal muscle contraction ? -
ANS plateau depolarization
cardiac action potential phases - ANS 1. rapid depolarization 2. plateau depolarization 3.
repolarization
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, P-wave - ANS produced by atrial depolarization
QRS complex - ANS produced by ventricular depolarization; atrial repolarization
T-wave - ANS produced by ventricular repolarization
Blood leaves the arterial system _______ through the capillaries and enters _____ from the
heart - ANS continuously; intermittently
during systole.... - ANS ventricles contract; semilunar valves open; blood flows into the
arterial system; arteries are stretched and blood pressure increases
systolic pressure: - ANS peak pressure reached during the cardiac cycle
diastolic pressure: - ANS arterial blood pressure is at its lowest;immediately before
contracting ventricle pushes blood into the arteries again; relaxation of the ventricles
dicrotic notch - ANS small plateau or dip in the pressure wave is caused by the closure of the
aortic valve
"lub" sound - ANS occurs during the early phase of ventricular contraction. produced by the
closing of the atrioventricular (mitral and tricuspid valves)
"dup" sound - ANS ventricles relax and blood pressure drops below that in the artery and the
semilunar valves (aortic and pulmonary) close
In the resting state, atrial systole accounts for ____ of atrial filling. - ANS 20%
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QUESTIONS AND ANSWERS
Electrocardiogram ECG - ANS pattern of electrical activity recorded at the body surface
Cardiac Contractions are _______ on a nerve supply - ANS not dependent
Innervations by the _______ and ________ nerves modify the basic cardiac rhythms -
ANS parasympathetic;sympathetic; (thus the central nervous system can affect the rhythm
sinus arrhythmia - ANS respiratory activity affects the heart rate
sinoatrial node - ANS pacemaker of the heart
atrioventricular node - ANS the only electrical connection between the atria and the
ventricles
electrical stimulation through action potentials through the heart - ANS SA node --> AV node
(slowly to allow atrial contraction to contribute to ventricular filling)--> rapidly through the AV
bundle -- > Purkinje fibers to excite both ventricles
what aspect of cardiac action potential distinguishes it from skeletal muscle contraction ? -
ANS plateau depolarization
cardiac action potential phases - ANS 1. rapid depolarization 2. plateau depolarization 3.
repolarization
Copyright ©2025 BRIGHTSTARS ALL RIGHTS RESERVED 1
, P-wave - ANS produced by atrial depolarization
QRS complex - ANS produced by ventricular depolarization; atrial repolarization
T-wave - ANS produced by ventricular repolarization
Blood leaves the arterial system _______ through the capillaries and enters _____ from the
heart - ANS continuously; intermittently
during systole.... - ANS ventricles contract; semilunar valves open; blood flows into the
arterial system; arteries are stretched and blood pressure increases
systolic pressure: - ANS peak pressure reached during the cardiac cycle
diastolic pressure: - ANS arterial blood pressure is at its lowest;immediately before
contracting ventricle pushes blood into the arteries again; relaxation of the ventricles
dicrotic notch - ANS small plateau or dip in the pressure wave is caused by the closure of the
aortic valve
"lub" sound - ANS occurs during the early phase of ventricular contraction. produced by the
closing of the atrioventricular (mitral and tricuspid valves)
"dup" sound - ANS ventricles relax and blood pressure drops below that in the artery and the
semilunar valves (aortic and pulmonary) close
In the resting state, atrial systole accounts for ____ of atrial filling. - ANS 20%
Copyright ©2025 BRIGHTSTARS ALL RIGHTS RESERVED 2
